SCIENTIFIC NOTES. 143 



name of Callimome Devoniensis. Mr. D'Urban did not think that the 

 galls occasioned much injury to large oaks, but to young trees they are 

 very injurious, frequently distorting the leading shoot, and seriously 

 retarding its growth. They make their appearance on the oaks in this 

 neighbourhood early in July, and growing rapidly reach their full size 

 in August. They are formed on the young shoots of the year, always 

 in the centre of a bud, and are monotholasmous, that is, they contain 

 a single individual only. Some of them produce the flies in September, 

 nearly all being females. The males are remarkably scarce, and have 

 but rarely been obtained. Some remain in the larva state within the 

 gall all through the winter, and emerge in the spring. Few, however, 

 of those hybernating escape the different species of tit, those little birds 

 picking the hard galls to pieces to get at the fat white grub inside. The 

 galls themselves are very persistent, remaining for several years on the 

 trees. Those from which the fly has escaped may readily be known by 

 the presence of a single round hole on one side. Mr. D'Urban then 

 explained the manner in which galls are formed, and the mechanism 

 of the instrument with which the gall-fly makes a puncture in the bark 

 of the trunk or shoots, in the young bud, on the leaf, or on the 

 peduncles of the flowers, according to the part of the tree selected by a 

 particular species, of which a great many infest the oak. 



Albumen from Fish Spawn. — Some years ago La Society Indus- 

 trielle at Mulhausen (Alsace) offered a prize of the gold medal of the 

 Society for the invention of some substitute for albumen prepared from 

 eggs ; and further, 17,800 francs as a remuneration for the first manu- 

 facture, on a large scale, of such a substitute. The prize was gained in 

 1860, by J. G. Leuchs, of Nuremburg, and who has a patent for extract- 

 ing lbumen from fishes' roe, spawn, &c. The albumen thus gained is 

 a complete substitute for that of hen's eggs, contains even less water, 

 and is much cheaper. Some exhibited in the Swedish Court, made by 

 Sahlstrom, of Jonkopine, is 2s. 4^d. per lb. For certain purposes, 

 the fat is separated from the albumen, which then no longer retains 

 the smell of raw fish. This fat is used for grease. The residue of 

 fishes' spawn, after the albumen has been extracted, is used in the 

 manufacture of ammonia, prussiate of potash, &c. 



Algerian Silk.— For many years past the silk-worm has been attacked 

 by disease, and in all the productive countries the harvest has been 

 sensibly diminished. The Algerian cultivators have particularly 

 suffered by this state of things, and the Administration, which had 

 engaged to pay to the spinners a sum of 12 francs per kilogramme of 

 silk spun from Algerian cocoons, have so far modified their first decision 

 as without diminishing the bounty offered, to permit the spinners to 

 buy elsewhere the cocoons they require to keep their factories going. 

 The results of the silk operations in Algiers in 1861 were as follows : — 

 Number of breeders, 257 ; quantity of cocoons raised, 4,206 kilo- 

 grammes, from 15,253 grammes of eggs ; sum paid to the spinners by 

 the Government, 25,588 francs. 



